Electrosurgical instruments are well known and widely used in the medical, dental, and veterinarian fields. They offer the capability of precision cutting with electrosurgical currents in the megacycle range using a handpiece with needle, ball, or loop electrodes in a unipolar operating mode, or convenient coagulation using a forceps in a bipolar operating mode. Ellman International, Inc. makes available an electrosurgical instrument which provides on its front panel connectors for receiving the plug of a unipolar handpiece and a ground or indifferent plate, as well as connectors for receiving the plugs of a bipolar forceps.
In a typical surgical setting, a surgeon may first use the unipolar handpiece to perform a desired cutting procedure and then desire to use the bipolar forceps for coagulation of blood vessels because of its unique ability to coagulate in a fluid field. This creates problems in maintaining the requisite sterile field while still allowing the surgeon to unplug and plug in different devices from or to the instrument. One possible solution is described in U.S. Pat. No. 5,562,503, whose contents are herein incorporated by reference. In the solution proposed in this patent, an adaptor apparatus is provided and configured to plug directly into the connectors on the electrosurgical instrument, and provided with connector means for receiving mating connectors of both the unipolar handpiece and the bipolar forceps. Switch means are provided on the adaptor apparatus for allowing the surgeon to easily switch over from the unipolar to the bipolar mode by simply throwing the switch. Since the adaptor can be attached to the electrosurgical instrument and the unipolar handpiece and bipolar forceps both attached to the adaptor before the sterile field is created, only the switch handle need be touched to switch between the two modes, and the switch handle can easily be sterilized. Alternatively, the surgeon can use an elbow to throw the switch without spoiling the sterile field.
However, the instrument described in this patent uses a single frequency for the operating modes when using either a unipolar handpiece or a bipolar handpiece. This is not always optimum for both cutting and coagulation. Moreover, certain applications require an instrument which provides high output radio-frequency (RF) energy for delicate, precise, and quick-healing cutting procedures, but with low leakage currents. To the best of our knowledge, there is no commercially-available instrument that provides high output radio-frequency (RF) energy for delicate, precise, and quick-healing cutting procedures with low leakage currents using a unipolar handpiece, and also provides high-quality RF energy best suited for coagulation for use with a bipolar handpiece.